I am only giving this two stars because although it was shipped very fast, the bag I received was broken, the seal was open, and most of my seeds spilled out. My rating is not based on whether it works or not because I have not tried it yet and will not try it until I hopefully get a new bag from iHerb. I have recently sent two emails to customer service and I am waiting for their response.
I will update this review once I actually try the product.